Variable var->pixclock can be set by user. In case it equals to
zero, divide by zero would occur in get_var_refresh.
Similar crashes have happened in other fbdev drivers. We fix this
by checking whether 'pixclock' is zero.
Similar commit: commit 16844e58704 ("video: fbdev: tridentfb:
Error out if 'pixclock' equals zero")
Signed-off-by: Alex Guo <[email protected]>
---
drivers/video/fbdev/via/viafbdev.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/via/viafbdev.c
b/drivers/video/fbdev/via/viafbdev.c
index 6da5ae7d229a..5b58e93f8c28 100644
--- a/drivers/video/fbdev/via/viafbdev.c
+++ b/drivers/video/fbdev/via/viafbdev.c
@@ -179,6 +179,8 @@ static inline int get_var_refresh(struct fb_var_screeninfo
*var)
+ var->hsync_len;
vtotal = var->upper_margin + var->yres + var->lower_margin
+ var->vsync_len;
+ if (!var->pixclock)
+ return -EINVAL;
return PICOS2KHZ(var->pixclock) * 1000 / (htotal * vtotal);
}
--
2.34.1
